Signal indicating device



May 22, 1956 H. w. PARMER SIGNAL INDICATING DEVICE 2 Sheets-Sheet 2 Filed April 2, 1953 INVENTOR.

HARRY W. PARMER fif/a United States Patent SIGNAL INDICATING DEVICE Harry W. Parmer, Elberon, N. J. Application April 2, 1953, Serial No. 346,550 6 Claims. (Cl. 200-93) (Granted under 'Iitle 35, U. S. Code (1952), see. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment of any royalty thereon.

This invention relates to a new and useful actuator for an indicator or relay used in such devices as telephone switchboards, etc., and has for its principal object to provide an actuator operable by a momentary energization of very low power to retain an actuation corresponding to the last impulse which was effective in operating the device. Another object of the invention is to provide a lost motion connection between the armature or rotor of the actuator and the switch or relay contacts operated thereby in order that the rotor can acquire some kinetic energy of rotation, and also move into a position where the energizing flux from the relay coil pulls strongly on the rotor, and therefore is in the best possible condition to perform the switching function in a positive manner. This has been accomplished by a polarized device, and therefore has further advantages when this characteristic is also to be used. These and other objects of the invention will be more apparent from the following description and claims.

The invention will be more fully understood from the drawing in which:

Fig. 1 is a general view of the device with the moving parts shown in partially exploded position;

Fig. 2 is an assembled view of the moving parts in one of the two positions of rest; and

Fig. 3 is a general view of a similar device with a more complex switch with the moving parts shown in partially exploded position.

Figs. 4, 5, and 6 show a variety of circuits in which the device may be used.

In Fig. 1 there is shown an operating coil 12 which may include a single winding or a plurality of windings depending on the use to be made of the device; terminals 14, i6, 18, and 20 are shown to illustrate suitable connections to the coil. Within the coil there is a high permeability core member 22 which can be made longitudinally adjustable by some means such as a threaded surface 24 thru end plate 25 held by check nut 26 for a purpose which will be later described. In line with the end of the core is a rotor member 27 of which the major element is a ring 28 which may be permanently magnetized and the remainder is merely a casing 30 which may be formed of luminescent plastic with one side obscured by opaque paint or otherwise marked in order that its rotational position may be readily observed. This rotor is supported on an axle 32 retained between two yoke members 34 and 36 formed on the edges of a washer cast in end plate 37 and in this form may be considered as a complete indicator device, although a casing of magnetic material may be used as the flux return path from the core.

The permanent magnet of the rotor will cause it to remain in a position with one of its poles close to the core of the coil. However, when the current in the coil is of such a direction and magnitude that the flux due to the current overbalances the flux due to the permanent magnet of the rotor, the pole of the rotor then adjacent to the core is repelled; as soon as it has moved a small angle in either direction, the other pole of the rotor is attracted by the core and moves the rotor into the alternate position with a very positive action. By adjusting the position of the core relative to the rotor it is very simple to determine the precise value of current at which the unit can be made to operate. It will be noted that the flux due to the rotor magnet need only be slightly overcome by the flux due to the current in the coil, and once the rotation is started the rotor flux and flux due to the coil tend to add up in moving the rotor positively to the final position; also during the initial part of the movement the rotor is building up a certain amount of kinetic energy which assists in moving the rotor to such final position. These effects may be utilized to operate a switching mechanism such as a butterfly type switch or the cam or roller operated switches often used in telephone work.

The operation of the switch as shown in Figs. 1 and 2 of the drawing involves the use of a pin 38 on the rotor which moves within the large opening 49 of the butterfly member 41, having raised contacts 42 and 43 on one side and 44 and 45 on the other side and another smaller opening 46 opposite the opening 40. The contacts 42 and 43 of this butterfly member are pressed against the stationary contact support member 48 having any desired arrangement of contacts such as 50, 52, 54, etc., by a spring 56 on the axle pushing a disc 57 against contacts 44 and 45; it may be noted that the axle member is similar to the members commonly used for holding watch bracelets and therefore the entire rotor and switch assem bly may be readily removed from the yoke members for any necessary servicing. A solid pin which can be pushed thru the yoke member 34 but pushes against yoke member 36 provides a better bearing than the short pin construction often used in watches. The yoke member 34 also has a pin 58 which extends within the smaller opening 46 of the butterfly member to prevent excessive rotation beyond the intended poistions and a bushing member 59 for the contact support member 48.

The contacts 50, 52, and 54 may be provided in any suitable manner such as the printed circuit now in common use, and are provided with eyelets 6t 63, and 64 to which leads are soldered and connected to terminals 70, 72, and 74 at the end of the unit. Since the switch mem ber 44 is connected to the axle it is also desirable to have a lead from the yoke member 36 to one of the terminals at the end of the unit. One function of the switch may be to disconnect the energizing coil since it need not be energized once the rotor has operated.

The rotor may be formed most economically by using a disc, washer, or ring of material which may be permanently magnetized, and casting the rotor of a suitable luminescent plastic material about the ring and the pin 38. The pin 38 may then be used as the guide means for holding the rotor in a suitable position between the poles of a powerful magnet in order that it may be magnetized in the proper direction and also in covering part of the surface with opaque paint.

The switch as shown in Fig. 3 of the drawing is suitable for more complex switching functions or if larger currents are to be controlled and involves the use of a pin 38 thru the rotor or formed on its sides which moves within the large opening 40 and 40" of the roller support member 39 with cross members 47 and 47', rollers 33 and 35 and,

opposite the openings 40' and 40", smaller openings 46" and 46" in which the stop pins 58' and 58" are located. The rollers are used to operate the various contacts 51, 53, etc., between the stationary contact members 55, 57, 59, 61, etc. The ends of the moving contacts 51 and 53 are so formed that the roller support member will remain in its last operated position until the rotor provides the necessary mechanical impulse for moving the roller. The energy stored ineither one of the moving contact springs 51and 53 is returned to the roller and its support member during the next operation and helps to reset the contact on the other side of the switch.

In the particular form shown the core 22 is made flat and is provided with a return magnetic circuit 23, the yokes 34 and 36 are made as a part of the end plate 37', and the contacts are supported in a block of insulation 49, mounted on the sides of member 23.

Fig. 4 illustrates a telephone circuit in which lifting receiver 84 at a subscriber station 86 draws current from battery 88 thru resistor 90 and line coil 92 to actuate the device, and connects restoring coil 94 thru switch contacts 96 to substantially neutralize the effect of the line coil. However the device stays in operated position until the receiver is replaced to deenergize the line coil 92 and permit restoring coil 94 to actuate the device back to its original position and disconnect switch 96 to avoid further battery drain.

Fig. illustrates a circuit involving no battery drain except during each actuation. Actuation by operating coil 92 under control of switch contact 85 disconnects such coil at switch contact 95 and connects restoring coil 94 at switch contact 96 in preparation for a restoring actuation under control of switch contact 87. Both these circuits require appropriate polarity of connections for proper operation but reversal of polarity will make the device inoperative or at least different in operation.

Fig. 6 illustrates a circuit which involves no battery drain except during each actuation, and is controlled only by reversal of polarity. A double battery 88', 88", and switch contacts 85' and 87 or other suitable means to provide a reversal of polarity determines the direction of current flow in the single operating coil 92". The switch contacts 95 and 96" are arranged to connect suitable rectifiers 98 and 99 in the circuit, of such polarity that a continuation of the voltage which has actuated the device meets a high resistance and reduces the current in the coil, while a reversed voltage of proper magnitude meets a low resistance and readily restores the device.

With a unit approximately inch square and 3 /2 inches long overall having a butterfly type of switch it is quite practical to obtain very reliable operation on a current of 4 milliamperes for second thru 16,000 turns of wire in either of two coils, the inner one of about 1,000 ohms, the outer one of about 2,000 ohms. With a unit about 1 /2 by by 3 /2 inches, having a roller operated switch with eight sets of double pole double throw contacts, approximately double this energy has been found to be adequate. If operation at a particular value of current is desirable, the position of core 22 relative to the rotor 27 may be adjusted by using the threaded surface 24.

Preferred embodiments of the invention have been described in slightly simplified form to facilitate an understanding of the features of the invention, but many variations will be apparent to those skilled in the art. What is claimed is:

1. A magnetic circuit including a high permeability member and a relatively rotatable permanent magnet member to provide a flux through the circuit suflicient to retain said members in either of two positions of rest differing by nearly 180 relative rotation, operating coil means energizable to provide a magnetomotive force in either direction in said first member to modify said flux in the corresponding position of rest by opposing said flux from said second member to start relative rotation of said members and then aiding said flux from said second member to complete rotation to the other position of rest, and switch means operable by said relative rotation of said members including a lost motion connection permitting said relative rotation to occur freely until nearly completed and then utilizing the kinetic energy of IO- tation and the aiding relation of said magnet and said operating means to actuate said switch means near the end of the rotation of the members, said switch means including two alternately set spring contacts, the setting of one said contact at said one position of rest storing mechanical energy which is used in setting the other said contact at said other position of rest, said switching means being connected to said operating coil means to cancel the energization in the direction in which the coil has been en ergized to cause relative rotation when said rotation is substantially accomplished.

2. A magnetic circuit including a high permeability member and a relatively rotatable permanent magnet member to provide a flux through the circuit sufficient to retain said members in either of two positions of rest differing by nearly relative rotation, operating coil means energizable to provide a magnetomotive force in either direction in said first member to modify said flux in the corresponding position of rest by opposing said flux from said second member to start relative rotation of said members and then aiding said flux from said second member to complete rotation to the other position of rest, and switch means operable by said relative rotation of said members including a lost motion connection permitting said relative rotation to occur freely until nearly completed and then utilizing the kinetic energy of rotation and the aiding relation of said magnet and said operating means to actuate said switch means near the end of the rotation of the members, said switch means being connected to said operating coil means to cancel the energization in the direction in which the coil has been energized to cause relative rotation when said rotation is substantially accomplished.

A magnetic circuit including a high permeability member and a relatively rotatable permanent magnet member to provide a flux through the circuit sufiicient to retain said members in either of two positions of rest differing by nearly 180 relative rotation, operating coil means energizable to provide a magnetomotive force in either direction in said first member to modify said fiux in the corresponding position of rest by opposing said flux from said second member to start relative rotation of said members and then aiding said flux from said second member to complete rotation to the other position of rest, and switch means operable by said relative rotation of said members including two alternately set spring contacts, the setting of one said contact at said one position of rest storing mechanical energy which is used in setting the other said contact at said other position of rest, said switching means being connected to said operating coil means to cancel the energization in the direction in which the coil has been energized to cause relative rotation when said rotation is substantially accomplished.

4. A magnetic circuit including a high permeability member and a relatively rotatable permanent magnet member to provide a flux through the circuit sufiicient to retain said members in either of two positions of rest difiering by nearly 180 relative rotation, operating coil means energizable to provide a magnetomotive force in either direction in said first member to modify said fiux in the corresponding position of rest by opposing said flux from said second member to start relative rotation of said members and then aiding said flux from said second member to complete rotation to the other position of rest, and switch means operable by said relative rotation of said members including a lost motion connection permitting said relative rotation to occur freely until nearly completed and then utilizing the kinetic energy of rotation and the aiding relation of said magnet and said operating means to actuate said switch means near the end of the rotation of the members, said switch means including two alternately set spring contacts, the setting of one said contact at said one position of rest storing mechanical energy which is used in setting the other said contact at said other position of rest.

5. A magnetic circuit including a high permeability member and a relatively rotatable permanent magnet member to provide a flux through the circuit sufiicient to retain said members in either of two positions of rest differing by nearly 180 relative rotation, operating coil means energizable to provide a magnetomotive force in either direction in said first member to modify said flux in the corresponding position of rest by opposing said flux from said second member to start relative rotation of said members and then aiding said flux from said second member to complete rotation to the other position of rest, and switch means operable by said relative rotation of said members including a lost motion connection permitting said relative rotation to occur freely until nearly completed and then utilizing the kinetic energy of rotation and the aiding relation of said magnet and said operating means to actuate said switch means near the end of the rotation of the members.

6. A magnetic circuit including a high permeability member and a relatively rotatable permanent magnet member to provide a flux through the circuit sufficient to retain said members in either of two positions of rest differing by nearly 180 relative rotation, operating coil means energizable to provide a magnetomotive force in either direction in said first member to modify said flux in the corresponding position of rest by opposing said flux from said second member to start relative rotation of said members and then aiding said flux from said second member to complete rotation to the other position of rest, and switch means operable by said relative rotation of said members said switch means including a pair of alternately set spring contacts, the setting of one said contact at said one position of rest storing mechanical energy which is used in setting the other said contact at said other position of rest.

References Cited in the file of this patent UNITED STATES PATENTS 574,045 Scribner Dec. 29, 1896 1,445,951 Hoffman Feb. 20, 1923 1,949,994 Dyktor et al Mar. 6, 1934 1,883,766 Cox et al. Oct. 18, 1932 2,140,604 Snavely Dec. 20, 1938 2,175,046 Warner Oct. 3, 1939 2,415,452 Taylor Feb. 11, 1947 2,574,403 Lloyd Nov. 6, 1951 2,585,974 Taylor Feb. 19, 1952 2,632,072 Zellner Mar. 17, 1953 FOREIGN PATENTS 744,148 France Apr. 12, 1933 

